1. Field of the Invention
This invention is provided in order to expand the performance of a piano by automatically and instantaneously shifting the musical scale of a piano to another musical scale.
2. Description of the Prior Art
A piano is tuned to an even temperament musical scale. However, music in the world is often tuned in an individual musical scale obtained by making and originating a natural represented tone as a fundamental and such fundamental tone has been selected differently at different times and by racial and regional characteristics (hereinafter referred to as a natural represented tone type musical scale). This music cannot be reproduced vividly unless the respective musical scale is used.
In these types of musical scales, if the fundamental note of the musical scale changes, the intervals between the notes of the musical scale will change so that the variety of tones is increased, and in the case of a piano, the number of keys must be increased. As a result, if a piano remains unchanged, then it cannot be put to practical use for such music by reason of the mechanism and playing technique.
An even temperament has been devised artificially in order to prevent the above-described difficulties. But an even temperament has such insufficiencies that the beauty of tones, particularly at the point of chords, is inferior in comparison with a natural represented tone. These insufficiencies are recognized in acoustics in both physics and music.